KR102473610B1 - Adhesive composition, adhesive layer and optical member with adhesive layer - Google Patents

Abstract

A pressure-sensitive adhesive composition containing 100 parts by weight of a (meth)acrylic resin (A) and 0.15 to 8 parts by weight of a compound (B) containing at least one double bond and at least one alkylenedioxy group in a molecule, a pressure-sensitive adhesive layer containing the same, and An optical member with a pressure-sensitive adhesive layer provided with the pressure-sensitive adhesive layer is provided. The alkylenedioxy group may be, for example, a straight-chain or branched alkylenedioxy group having 1 to 3 carbon atoms.

Description

Adhesive composition, adhesive layer, and optical member with adhesive layer {ADHESIVE COMPOSITION, ADHESIVE LAYER AND OPTICAL MEMBER WITH ADHESIVE LAYER}

The present invention relates to a pressure-sensitive adhesive composition, a pressure-sensitive adhesive layer containing the pressure-sensitive adhesive composition, and an optical member including the pressure-sensitive adhesive layer.

A polarizing plate formed by laminating and bonding a protective film on one side or both sides of a polarizer is an image display device such as a liquid crystal display device and an organic electroluminescent (organic EL) display device, particularly recently mobile phones, smartphones, and tablet terminals. It is an optical member widely used in various mobile devices such as An optical member such as a polarizing plate is often used by being bonded to another member (for example, an optical member such as a liquid crystal cell in a liquid crystal display device) through an adhesive layer (see, for example, Japanese Unexamined Patent Publication No. 2010-229321). For this reason, in many cases, for example, a polarizing plate is distributed on the market in the form of a polarizing plate with an adhesive layer in which an adhesive layer is previously provided on one side thereof.

Reworkability is requested|required of the adhesive composition used for the adhesive layer for bonding optical members. After bonding the optical member to another member via the pressure-sensitive adhesive layer, if any problem is found, in order to reuse the other member, a rework operation is performed in which the bonded optical member with the pressure-sensitive adhesive layer is peeled off and a new optical member is reattached. Because there are times when this is necessary. The rework property means the peelability at the time of peeling and removing the optical member for each adhesive layer in this rework operation, and in the other member after peeling, a dark part, glue residue, etc. are left on the surface to which the adhesive layer was bonded. If there is almost no and the optical member with an adhesive layer can be easily reattached to the surface, it is considered to have excellent reworkability.

In addition, durability is also required for the pressure-sensitive adhesive composition. That is, the pressure-sensitive adhesive layer formed on the image display device or the like may be placed under a high-temperature or high-temperature, high-humidity environment, or under an environment in which high and low temperatures are repeated. It is required to be able to suppress problems that may occur according to. As this problem, there exist floating or peeling at the interface of the adhesive layer and the member adjacent to this, and foaming of the adhesive layer.

However, the pressure-sensitive adhesive composition for optics disclosed in Patent Literature 1 was not necessarily satisfactory regarding both durability and reworkability of the pressure-sensitive adhesive layer. Then, this invention aims at provision of the adhesive composition with which durability and reworkability are compatible, the adhesive layer containing it, and the optical member with an adhesive layer provided with this adhesive layer.

This invention provides the adhesive composition described below, an adhesive layer, and the optical member with an adhesive layer.

[1] (meth) acrylic resin (A) 100 parts by weight,

0.15 to 8 parts by weight of a compound (B) containing at least one double bond and at least one alkylenedioxy group in the molecule

An adhesive composition containing a.

[2] The pressure-sensitive adhesive composition according to [1], wherein the compound (B) has a molecular weight of 3000 or less.

[3] The pressure-sensitive adhesive composition according to [1] or [2], wherein the alkylenedioxy group is a straight-chain or branched alkylenedioxy group having 1 to 3 carbon atoms.

[4] The pressure-sensitive adhesive composition according to any one of [1] to [3], wherein the alkylenedioxy group is an ethylenedioxy group.

[5] The adhesive composition according to any one of [1] to [4], wherein the compound (B) contains a compound (B-1) represented by the following formula (B-1):

(In the formula, h represents an integer of 1 to 6, Q ¹ represents a hydrogen atom or a methyl group, and Q ⁰ represents an h-valent group having at least one alkylenedioxy group.)

[6] The adhesive composition according to [5], wherein the compound (B-1) is a compound (B-1a) represented by the following formula (B-1a):

(Wherein, Q ¹ represents a hydrogen atom or a methyl group, L represents a single bond or an alkylene group having 1 to 4 carbon atoms, i represents an integer of 1 to 50, and Q ² is substituted with an alkoxy group having 1 to 3 carbon atoms, Represents an alkyl group, aryl group or aralkyl group having 1 to 4 carbon atoms, which may be present.)

[7] The pressure-sensitive adhesive composition according to any one of [1] to [6], wherein the (meth)acrylic resin (A) has a weight average molecular weight (Mw) of 500,000 to 1,700,000.

[8] further contains a crosslinking agent (C),

The adhesive composition according to any one of [1] to [7], wherein the content of the crosslinking agent (C) is 0.1 to 5 parts by weight based on 100 parts by weight of the (meth)acrylic resin (A).

[9] further contains an ionic compound (D),

The adhesive composition according to any one of [1] to [8], wherein the content of the ionic compound (D) is 0.3 to 5 parts by weight based on 100 parts by weight of the (meth)acrylic resin (A).

[10] A pressure-sensitive adhesive layer containing the pressure-sensitive adhesive composition according to any one of [1] to [9].

[11] An optical member with a pressure-sensitive adhesive layer comprising an optical member and the pressure-sensitive adhesive layer according to [10] laminated thereon.

[12] The optical member with an adhesive layer according to [11], wherein the optical member includes a polarizer.

[13] The optical member with a pressure-sensitive adhesive layer according to [11] or [12], further comprising a release film laminated on the outer surface of the pressure-sensitive adhesive layer.

[14] When the peel force of the release film after the heat test maintained at 70 ° C. for 20 days is P ₁ and the peel force before the heat test is P ₀ , the peel force enhancement rate defined by the following formula is 200% or less, [ 13] the optical member with a pressure-sensitive adhesive layer:

Peel force enhancement rate (%) = (P ₁ /P ₀ )×100

[15] The optical member with a pressure-sensitive adhesive layer according to [11] or [12], further comprising a glass substrate laminated on the outer surface of the pressure-sensitive adhesive layer.

ADVANTAGE OF THE INVENTION According to this invention, the adhesive composition in which durability and reworkability are compatible, the adhesive layer containing it, and the optical member with an adhesive layer provided with this adhesive layer can be provided.

1 is a schematic sectional view showing an example of an optical member with a pressure-sensitive adhesive layer according to the present invention.
Fig. 2 is a schematic sectional view showing another example of an optical member with a pressure-sensitive adhesive layer according to the present invention.
Fig. 3 is a schematic cross-sectional view showing still another example of an optical member with a pressure-sensitive adhesive layer according to the present invention.
Fig. 4 is a schematic cross-sectional view showing still another example of an optical member with a pressure-sensitive adhesive layer according to the present invention.

<Adhesive composition>

(1) (meth)acrylic resin (A)

It is preferable that (meth)acrylic-type resin (A) contains (meth)acrylic-type resin (A-1) which is a polymer whose main component is a structural unit derived from a (meth)acrylic acid ester represented by the following formula (I). :

In the present specification, "(meth)acryl" means acryl and/or methacryl, and "(meth)" when referring to (meth)acrylate, (meth)acryloyl, etc. has the same meaning.

In the above formula (I), R ¹ represents a hydrogen atom or a methyl group, R ² may be substituted with an alkyl group having 1 to 14 carbon atoms, which may be substituted with an alkoxy group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms. Represents an aralkyl group having 7 to 21 carbon atoms. It is preferable that R ^<2> is a C1-C14 alkyl group which may be substituted by the C1-C10 alkoxy group.

Specific examples of the (meth)acrylic acid ester represented by the formula (I) include linear acrylic acid alkyl esters such as methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, n-octyl acrylate, and lauryl acrylate; branched acrylic acid alkyl esters such as isobutyl acrylate, 2-ethylhexyl acrylate, and isooctyl acrylate; linear methacrylic acid alkyl esters such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, n-octyl methacrylate, and lauryl methacrylate; and branched methacrylic acid alkyl esters such as isobutyl methacrylate, 2-ethylhexyl methacrylate, and isooctyl methacrylate.

When R ² is an alkyl group substituted with an alkoxy group, that is, when R ² is an alkoxyalkyl group, specific examples of the (meth)acrylic acid ester represented by formula (I) include 2-methoxyethyl acrylate and ethoxy acrylate. methyl, 2-methoxyethyl methacrylate, ethoxymethyl methacrylate, and the like. Specific examples of the (meth)acrylic acid ester represented by formula (I) in a case where R ² is an aralkyl group having 7 to 21 carbon atoms include benzyl acrylate, benzyl methacrylate, and the like.

The (meth)acrylic acid ester represented by Formula (I) may be used individually by 1 type, or may use 2 or more types together. Especially, it is preferable that (meth)acrylic acid ester contains n-butyl acrylate. It is preferable that (meth)acrylic-type resin (A-1) contains 50 weight% or more of n-butyl acrylate in all the monomers which comprise this. Of course, in addition to n-butyl acrylate, other (meth)acrylic acid esters represented by formula (I) may be used in combination.

The (meth)acrylic resin (A-1) is usually a copolymer of the (meth)acrylic acid ester of the formula (I) and at least one other monomer such as a monomer having a polar functional group. The monomer having a polar functional group is preferably a (meth)acrylic acid-based compound having a polar functional group. Examples of the polar functional group of the monomer include a free carboxyl group, a hydroxyl group, an amino group, and a heterocyclic group including an epoxy group.

Specific examples of the monomer having a polar functional group include monomers having a free carboxyl group such as acrylic acid, methacrylic acid, and β-carboxyethyl (meth)acrylate; (meth)acrylate 2-hydroxyethyl, (meth)acrylate 3-hydroxypropyl, (meth)acrylate 4-hydroxybutyl, (meth)acrylate 2-(2-hydroxyethoxy)ethyl, (meth)acrylic acid monomers having a hydroxyl group such as 2- or 3-chloro-2-hydroxypropyl and diethylene glycol mono(meth)acrylate; Acryloylmorpholine, vinylcaprolactam, N-vinyl-2-pyrrolidone, vinylpyridine, tetrahydrofurfuryl (meth)acrylate, caprolactone-modified tetrahydrofurfuryl acrylate, 3,4-epoxycyclohexyl monomers having a heterocyclic group such as methyl (meth)acrylate, glycidyl (meth)acrylate, and 2,5-dihydrofuran; and monomers having an amino group different from the heterocyclic ring such as aminoethyl (meth)acrylate, N,N-dimethylaminoethyl (meth)acrylate, and dimethylaminopropyl (meth)acrylate. The monomers having a polar functional group may be used alone or in combination of two or more.

Among the above, from the viewpoint of the reactivity of the (meth)acrylic resin (A-1), it is preferable to use a monomer having a hydroxyl group as one of the polar functional group-containing monomers constituting the (meth)acrylic resin (A-1). do. In addition to the monomer having a hydroxyl group, it is also effective to use a monomer having another polar functional group, such as a monomer having a free carboxyl group.

The (meth)acrylic resin (A-1) is a monomer having one olefinic double bond and at least one aromatic ring in the molecule (except for those corresponding to the above formula (I) or the monomer having the above polar functional group) ) may further contain a structural unit derived from Suitable examples include (meth)acrylic acid-based compounds having an aromatic ring. The (meth)acrylic acid-based compound having such an aromatic ring includes neopentyl glycol benzoate (meth)acrylate and the like, in particular, an aryloxyalkyl group such as a (meth)acrylic acid ester containing a phenoxyethyl group represented by the following formula (II) Preferred are (meth)acrylic acid esters having:

In the formula (II), R ³ represents a hydrogen atom or a methyl group, n represents an integer of 1 to 8, and R ⁴ represents a hydrogen atom, an alkyl group, an aralkyl group or an aryl group. When R ⁴ is an alkyl group, it may have about 1 to 9 carbon atoms, when it is an aralkyl group, it may have about 7 to 11 carbon atoms, and when it is an aryl group, it may have about 6 to 10 carbon atoms.

Examples of the C1-C9 alkyl group constituting R ⁴ in formula (II) include methyl, butyl, nonyl, and the like, and the C7-C11 aralkyl group include benzyl, phenethyl, naphthylmethyl, and the like, and the C6-C10 aralkyl group. Examples of the aryl group include phenyl, tolyl, naphthyl and the like, respectively.

Specific examples of the phenoxyethyl group-containing (meth)acrylic acid ester represented by formula (II) include 2-phenoxyethyl (meth)acrylate, 2-(2-phenoxyethoxy)ethyl (meth)acrylate, and ethylene oxide-modified (meth)acrylic acid ester of nonylphenol, (meth)acrylic acid 2-(o-phenylphenoxy)ethyl, etc. are included. The phenoxyethyl group-containing (meth)acrylic acid ester may be used alone or in combination of two or more. Among them, phenoxyethyl group-containing (meth)acrylic acid esters include 2-phenoxyethyl (meth)acrylate, 2-(o-phenylphenoxy)ethyl (meth)acrylate, and/or 2-(2-(meth)acrylic acid). It is preferable to include phenoxyethoxy)ethyl.

The (meth)acrylic resin (A-1) contains a structural unit derived from the (meth)acrylic acid ester represented by the above formula (I), based on the total solid content, usually 60 to 99.9% by weight, preferably It is contained in an amount of 80 to 99.6% by weight, and contains a structural unit derived from a monomer having a polar functional group in an amount of usually 0.1 to 20% by weight, preferably 0.4 to 10% by weight, and also contains a phenoxyethyl group ( A structural unit derived from a monomer having an aromatic ring such as meth)acrylic acid ester is usually contained in an amount of 0 to 40% by weight, preferably 6 to 12% by weight.

The (meth)acrylic resin (A-1) is a monomer other than a monomer having an aromatic ring such as the (meth)acrylic acid ester of formula (I) described above, a monomer having a polar functional group, and a (meth)acrylic acid ester containing a phenoxyethyl group. (hereinafter also referred to as other monomers) may contain a structural unit derived from. Examples of other monomers include structural units derived from (meth)acrylic acid esters having an alicyclic structure in the molecule, structural units derived from styrenic monomers, structural units derived from vinyl monomers, and a plurality of (meth)acrylic acid esters in the molecule. Structural units derived from monomers having a royl group, structural units derived from (meth)acrylamide compounds, and the like are exemplified. The other monomers may be used singly or in combination of two or more.

The alicyclic structure in the (meth)acrylic acid ester having an alicyclic structure in the molecule is a cycloparaffin structure having usually 5 or more carbon atoms, preferably about 5 to 7 carbon atoms. Specific examples of (meth)acrylic acid esters having an alicyclic structure include isobornyl (meth)acrylate, cyclohexyl (meth)acrylate, dicyclopentanyl (meth)acrylate, cyclododecyl (meth)acrylate, and (meth)acrylic acid. methylcyclohexyl, trimethylcyclohexyl (meth)acrylate, tert-butylcyclohexyl (meth)acrylate, cyclohexylphenyl (meth)acrylate, cyclohexyl α-ethoxyacrylate and the like.

Specific examples of the styrenic monomer include styrene; alkyl styrenes such as methyl styrene, dimethyl styrene, trimethyl styrene, ethyl styrene, diethyl styrene, triethyl styrene, propyl styrene, butyl styrene, hexyl styrene, heptyl styrene, and octyl styrene; halogenated styrenes such as fluorostyrene, chlorostyrene, bromostyrene, dibromostyrene, and iodostyrene; nitrostyrene, acetylstyrene, methoxystyrene, divinylbenzene, and the like.

Specific examples of the vinyl monomer include fatty acid vinyl esters such as vinyl acetate, vinyl propionate, vinyl butyrate, vinyl 2-ethylhexanoate, and vinyl laurate; vinyl halides such as vinyl chloride and vinyl bromide; vinylidene halides such as vinylidene chloride; nitrogen-containing aromatic vinyls such as vinylpyridine, vinylpyrrolidone, and vinylcarbazole; conjugated diene monomers such as butadiene, isoprene, and chloroprene; Acrylonitrile, methacrylonitrile, etc. are included.

Specific examples of the monomer having a plurality of (meth)acryloyl groups in the molecule include 1,4-butanedioldi(meth)acrylate, 1,6-hexanedioldi(meth)acrylate, and 1,9-nonanedioldi. (meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, and tripropylene glycol di(meth)acrylate. a monomer having a (meth)acryloyl group; and monomers having three (meth)acryloyl groups in the molecule such as trimethylolpropane tri(meth)acrylate.

Specific examples of the (meth)acrylamide compound include N-methylol (meth)acrylamide, N-(2-hydroxyethyl)(meth)acrylamide, and N-(3-hydroxypropyl)(meth)acrylamide. , N-(4-hydroxybutyl)(meth)acrylamide, N-(5-hydroxypentyl)(meth)acrylamide, N-(6-hydroxyhexyl)(meth)acrylamide, N,N- Dimethyl(meth)acrylamide, N,N-diethyl(meth)acrylamide, N-isopropyl(meth)acrylamide, N-(3-dimethylaminopropyl)(meth)acrylamide, N-(1,1 -Dimethyl-3-oxobutyl)(meth)acrylamide, N-[2-(2-oxo-1-imidazolidinyl)ethyl](meth)acrylamide, 2-acryloylamino-2-methyl- 1-Propanesulfonic acid, N-(methoxymethyl)acrylamide, N-(ethoxymethyl)(meth)acrylamide, N-(propoxymethyl)(meth)acrylamide, N-(1-methylethoxymethyl ) (meth) acrylamide, N- (1-methylpropoxymethyl) (meth) acrylamide, N- (2-methylpropoxymethyl) (meth) acrylamide [alias: N- (isobutoxymethyl) (meth) acrylamide )acrylamide], N-(butoxymethyl)(meth)acrylamide, N-(1,1-dimethylethoxymethyl)(meth)acrylamide, N-(2-methoxyethyl)(meth)acrylamide , N-(2-ethoxyethyl)(meth)acrylamide, N-(2-propoxyethyl)(meth)acrylamide, N-[2-(1-methylethoxy)ethyl](meth)acrylamide , N-[2-(1-methylpropoxy)ethyl](meth)acrylamide, N-[2-(2-methylpropoxy)ethyl](meth)acrylamide [alias: N-(2-isobutoxy) ethyl)(meth)acrylamide], N-(2-butoxyethyl)(meth)acrylamide, N-[2-(1,1-dimethylethoxy)ethyl](meth)acrylamide, and the like. Among them, N-(methoxymethyl)acrylamide, N-(ethoxymethyl)acrylamide, N-(propoxymethyl)acrylamide, N-(butoxymethyl)acrylamide, N-(2-methylpropanol) Poxymethyl)acrylamide is preferably used.

The (meth)acrylic resin (A-1) contains other monomers in a proportion of usually 0 to 20% by weight, preferably 0 to 10% by weight, based on the total amount of solid content thereof.

The (meth)acrylic resin (A-1) contains as a main component a structural unit derived from the (meth)acrylic acid ester represented by formula (I) as described above, and contains a structural unit derived from a monomer having a polar functional group. It may also contain two or more types of (meth)acrylic resins that optionally contain structural units derived from monomers having an aromatic ring. In addition, while having a structural unit derived from this (meth)acrylic resin (A-1) and a (meth)acrylic resin (A-2) different from it, for example, (meth)acrylic acid ester of formula (I) What mixed (meth)acrylic resin etc. which do not have a polar functional group may be used. A structural unit derived from a (meth)acrylic acid ester of formula (I) as a main component, containing a structural unit derived from a monomer having a polar functional group, and optionally containing a structural unit derived from a monomer having an aromatic ring ( The meth)acrylic resin (A-1) is a main component of the pressure-sensitive adhesive composition, and its content is preferably 60% by weight or more, preferably 80% by weight or more, based on the total weight of the (meth)acrylic resin (A).

The (meth)acrylic resin (A-1) preferably has a weight average molecular weight (Mw) of 500,000 to 1,700,000 in terms of standard polystyrene by gel permeation chromatography (GPC), and is in the range of 600,000 to 1,500,000. It is more preferable to be in When the Mw is 500,000 or more, the adhesiveness in a high-temperature, high-humidity environment is improved, and the possibility of floating or peeling between the member (for example, glass substrate) and the pressure-sensitive adhesive layer bonding the pressure-sensitive adhesive layer tends to decrease, and furthermore, reworkability is increased. It tends to improve. Moreover, if Mw is 1,700,000 or less, when the optical member with an adhesive layer is applied to a liquid crystal display device, even if the dimension of the optical member changes, since the adhesive layer follows the dimensional change and fluctuates, the brightness of the periphery of the liquid crystal cell and There is no difference between the brightness of the center, so white streaks and color unevenness tend to be suppressed. The molecular weight distribution represented by the ratio (Mw/Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is usually in the range of about 2 to 10.

Preferable Mw of (meth)acrylic resin (A-1) also differs depending on the material of the adhesive layer formation surface in the member (optical member) on which the adhesive layer made of the adhesive composition containing this is formed. Conventionally, the Mw of at least about 1,000,000 was required for the (meth)acrylic resin constituting the acrylic pressure-sensitive adhesive, but according to the pressure-sensitive adhesive layer containing the (meth)acrylic-based resin (A-1), the adhesive layer formation surface When composed of a film exhibiting a moisture permeability higher than about 300 g/(m 2 24 hr) under conditions of a temperature of 40° C. and a relative humidity of 90%, for example, a cellulose-based resin film, the Mw is about 500,000 to 1,000,000 Even if it is relatively small, the above effect can be obtained. When such a resin film with high water permeability is used as the pressure-sensitive adhesive layer formation surface, the Mw of the (meth)acrylic resin (A-1) may of course be a large value within the range of 1.7 million or less.

On the other hand, the surface on which the pressure-sensitive adhesive layer is formed is about 300 g / (m 2 24 hr) or less under the conditions of a temperature of 40 ° C. and a relative humidity of 90%, such as a linear or cyclic polyolefin resin film or a retardation film obtained by stretching them. When composed of a resin film showing moisture permeability, if the Mw of the (meth)acrylic resin (A-1) is small, when the pressure-sensitive adhesive layer is applied to a glass substrate or the like, there is a tendency that floating or peeling between them tends to occur. . Therefore, in this case, it is preferable that Mw of (meth)acrylic-type resin (A-1) is 600,000 or more. It is preferable that Mw is 600,000 or more also from a viewpoint of improving adhesiveness under high temperature, high humidity.

The (meth)acrylic resin (A) may be composed only of the relatively high molecular weight (meth)acrylic resin (A-1) described above, and in addition to that, a (meth)acrylic resin (A-3) other than that may be used in combination. Examples of the (meth)acrylic resin (A-3) include those having a structural unit derived from (meth)acrylic acid ester represented by the formula (I) as a main component and having an Mw in the range of 0.50,000 to 120,000. have.

The (meth)acrylic resin (A) (a mixture thereof when two or more types are combined) is dissolved in ethyl acetate and a solution adjusted to a concentration of 20% by weight is 20 Pa·s or less at 25 ° C., and furthermore 0.1 Those exhibiting a viscosity of -7 Pa·s are preferred. If the viscosity is 20 Pa·s or less, the adhesiveness in a high-temperature, high-humidity environment is improved, and the possibility of floating or peeling between the member (eg glass substrate) and the pressure-sensitive adhesive layer that bonds the pressure-sensitive adhesive layer tends to decrease, and furthermore There is a tendency for reworkability to be improved. Viscosity can be measured with a Brookfield viscometer.

The (meth)acrylic resin (A-1) and other (meth)acrylic resins that can optionally be used in combination can be prepared by known methods such as solution polymerization, bulk polymerization, suspension polymerization, and emulsion polymerization. can In the production of (meth)acrylic resin, a polymerization initiator is usually used. The polymerization initiator is used in an amount of about 0.001 to 5 parts by weight based on 100 parts by weight of all the monomers used in the production of the (meth)acrylic resin. In addition, the (meth)acrylic resin may be produced by a method of advancing polymerization with active energy rays such as ultraviolet rays, for example.

As the polymerization initiator, a thermal polymerization initiator or a photopolymerization initiator is used. Examples of the photopolymerization initiator include 4-(2-hydroxyethoxy)phenyl(2-hydroxy-2-propyl)ketone and the like. As a thermal polymerization initiator, for example, 2,2'-azobisisobutyronitrile, 2,2'-azobis (2-methylbutyronitrile), 1,1'-azobis (cyclohexane-1-carbonitrile) ), 2,2'-azobis (2,4-dimethylvaleronitrile), 2,2'-azobis (2,4-dimethyl-4-methoxyvaleronitrile), dimethyl-2,2'- azo compounds such as azobis(2-methylpropionate) and 2,2'-azobis(2-hydroxymethylpropionitrile); Lauryl peroxide, tert-butyl hydroperoxide, benzoyl peroxide, tert-butyl peroxybenzoate, cumene hydroperoxide, diisopropylperoxydicarbonate, dipropylperoxydicarbonate, tert-butylperoxy organic peroxides such as neodecanoate, tert-butylperoxypivalate, and (3,5,5-trimethylhexanoyl) peroxide; and inorganic peroxides such as potassium persulfate, ammonium persulfate, and hydrogen peroxide. In addition, a redox type initiator in which a peroxide and a reducing agent are used together can also be used as the polymerization initiator.

As a method for producing a (meth)acrylic resin, a solution polymerization method is preferable among the methods described above. One example of the solution polymerization method is to mix monomers and organic solvents, add a thermal polymerization initiator in a nitrogen atmosphere, and stir at about 40 to 90°C, preferably about 60 to 80°C for about 3 to 10 hours. In order to control the reaction, the monomer and/or the thermal polymerization initiator may be continuously or intermittently added during polymerization or may be added in a state dissolved in an organic solvent. Examples of organic solvents include aromatic hydrocarbons such as toluene and xylene; esters such as ethyl acetate and butyl acetate; aliphatic alcohols such as propyl alcohol and isopropyl alcohol; Ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone can be used.

(2) Compound (B) containing at least one double bond and at least one alkylenedioxy group in the molecule

The pressure-sensitive adhesive composition according to the present invention is a compound (B) containing at least one double bond and at least one alkylenedioxy group (-O-alkylene-O-) in a molecule [hereinafter also referred to as compound (B)] contains By containing the compound (B), an adhesive composition in which durability and reworkability are highly compatible can be obtained. Moreover, according to the pressure-sensitive adhesive layer composed of the pressure-sensitive adhesive composition containing the compound (B), the exfoliation force of the release film laminated on the surface of the pressure-sensitive adhesive layer with respect to the pressure-sensitive adhesive layer can be suppressed from being enhanced by heat. A preferred example of the double bond is a double bond contained in a (meth)acryloyl group, and a more preferred example is the pressure-sensitive adhesive composition of the present invention in an environment exposed to light, a relatively high temperature environment, and an oxygen-containing atmosphere. , It is a double bond contained in a methacryloyl group from the point which durability and reworkability do not fall easily even if it stores the adhesive layer of this invention and the optical member with an adhesive layer of this invention over a long period of time. Preferred examples of the alkylenedioxy group are C1-C4 alkylenedioxy groups, more preferably C1-C3 straight-chain or branched, from the viewpoint of coexistence of durability and reworkability and suppression of enhancement of peeling force. It is an alkylenedioxy group, More preferably, it is an ethylenedioxy group (-OC ₂ H ₄ -O-).

From the viewpoint of coexistence of durability and rework properties and suppression of enhancement of peeling force, the compound (B) preferably has a molecular weight of 3000 or less, for example, 2000 or less, more preferably 1700 or less, and still more preferably 1400 or less. Moreover, as for molecular weight, it is preferable that it is 400 or more, it is more preferable that it is 600 or more, and it is still more preferable that it is 1050 or more.

From the viewpoint of coexistence of durability, reworkability, and enhancement suppression of peeling force, the compound (B) is a compound (B-1) containing a (meth)acryloyl group represented by the following formula (B-1). It is preferable to contain, and more preferably to consist of compound (B-1):

In the formula, h represents an integer of 1 to 6, Q ¹ represents a hydrogen atom or a methyl group, and Q ⁰ represents an h-valent group having at least one alkylenedioxy group. Compound (B) may contain 2 or more types of compounds (B-1). h is preferably an integer of 1 to 3.

The h-valent group having at least one alkylenedioxy group represented by Q ⁰ may be an h-valent hydrocarbon group having at least one alkylenedioxy group, and is preferably a mono- to trivalent hydrocarbon group having at least one ethylenedioxy group. . As this hydrocarbon group, groups represented by the following Q ⁰¹ , Q ⁰² , Q ⁰³ and Q ⁰⁴ are exemplified.

In Q ⁰¹ , Q ² represents an alkyl group having 1 to 4 carbon atoms, an aryl group or an aralkyl group which may be substituted with an alkoxy group having 1 to 3 carbon atoms, L represents a single bond or an alkylene group having 1 to 4 carbon atoms, i represents an integer of 1 to 50 (for example, 1 to 30). The number of carbon atoms of the aryl group that can be Q ² is preferably 6 to 20, and the number of carbon atoms of the aralkyl group is preferably 7 to 20. In Q ⁰² , j represents an integer of 1 to 40 (for example, 1 to 30). In Q ⁰³ , y and z each independently represent an integer of 1 to 40 (eg, 1 to 30), and y+z may be an integer of 1 to 40 (eg, 1 to 30). In Q ⁰⁴ , e, f, and g each independently represents an integer of 1 to 20 (eg, 1 to 10), and e+f+g may be an integer of 1 to 30 (eg, 1 to 25).

As the compound (B-1) preferably used, a compound (B-1a) represented by the following formula (B-1a) is exemplified:

Compound (B) may contain 2 or more types of compound (B-1a). Compound (B-1a) is a compound wherein Q ⁰ in the formula (B-1) is Q ⁰¹ . Q ¹ , L, i, and Q ² in the formula represent the same meanings as above. In compound (B-1a), L is preferably a single bond, and i is preferably an integer of 7 to 35, more preferably an integer of 9 to 25. Q ² is preferably an alkyl group of 1 to 3 carbon atoms or an aryl group of 6 to 20 carbon atoms, and examples thereof include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, a phenyl group and a biphenyl group.

As specific examples of Compound (B-1a), Q ¹ , L, i, and Q ² are listed in Table 1 below.

Another example of the compound (B-1) preferably used is a compound wherein Q ⁰ in the formula (B-1) is Q ⁰⁴ . In this case, h in the formula (B-1) is 3. Compound (B) may contain 2 or more types of compounds in which Q ⁰ is Q ⁰⁴ . In Q ⁰⁴ , e+f+g is preferably an integer of 5 to 25.

Another example of the compound (B-1) preferably used is a compound wherein Q ⁰ in the formula (B-1) is Q ⁰³ . In this case, h in the formula (B-1) is 2. Compound (B) may contain 2 or more types of compounds in which Q ⁰ is Q ⁰³ . In Q ⁰³ , y+z is preferably an integer of 5 to 25.

Compound (B) is 0.15 to 8 parts by weight, preferably 0.3 to 7 parts by weight, more preferably 0.3 to 7 parts by weight, based on 100 parts by weight of the solid content of the (meth)acrylic resin (A) (the sum of these when two or more types are used). Preferably, it is blended in a proportion of 0.5 to 6 parts by weight (for example, 1 to 5 parts by weight). When the compounding amount of the compound (B) is within this range, both durability and reworkability can be realized, and the effect of suppressing the enhancement of the peeling force can be obtained.

(3) crosslinking agent (C)

The pressure-sensitive adhesive composition may further contain a crosslinking agent (C). The crosslinking agent (C) is a compound that crosslinks the (meth)acrylic resin (A) by reacting with a structural unit derived from a polar functional group-containing monomer in the (meth)acrylic resin (A). Specifically, an isocyanate-type compound, an epoxy-type compound, an aziridine-type compound, a metal chelate-type compound, etc. can be illustrated. Among these, isocyanate-based compounds, epoxy-based compounds and aziridine-based compounds have at least two functional groups in their molecules capable of reacting with the polar functional groups in the (meth)acrylic resin (A). A crosslinking agent (C) may be used individually by 1 type, and may use 2 or more types together.

An isocyanate-based compound is a compound having at least two isocyanato groups (-NCO) in a molecule. Specific examples of the compound include tolylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, naphthalene diisocyanate, triphenyl Methane triisocyanate etc. are mentioned. Further, adducts obtained by reacting these isocyanate compounds with polyols such as glycerol or trimethylolpropane, as well as those obtained by forming isocyanate compounds into dimers, trimers, or the like can also be used as the crosslinking agent (C). Two or more isocyanate compounds may be mixed and used.

An epoxy-based compound is a compound having at least two epoxy groups in a molecule. Specific compounds include, for example, bisphenol A type epoxy resin, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, glycerin diglycidyl ether, glycerin triglycidyl ether, and 1,6-hexanediol diglycidyl ether. Cydyl ether, trimethylolpropane triglycidyl ether, N,N-diglycidylaniline, N,N,N',N'-tetraglycidyl-m-xylenediamine, 1,3-bis(N, N'-diglycidyl aminomethyl) cyclohexane etc. are mentioned. A mixture of two or more types of epoxy-based compounds may also be used.

An aziridine-type compound is a compound which has at least two 3-membered ring skeletons in a molecule which are also called ethylenimine and consist of 1 nitrogen atom and 2 carbon atoms. As specific compounds, for example, diphenylmethane-4,4'-bis(1-aziridinecarboxamide), toluene-2,4-bis(1-aziridinecarboxamide), triethylenemelamine, isophthaloyl Bis-1-(2-methylaziridine), tris-1-aziridinylphosphine oxide, hexamethylene-1,6-bis(1-aziridinecarboxamide), trimethylolpropane-tris-β-azi Ridinyl propionate, tetramethylolmethane-tris-β-aziridinyl propionate, etc. are mentioned. Two or more types of aziridine-based compounds may be mixed and used.

Examples of the metal chelate compound include compounds in which acetylacetone or ethyl acetoacetate is coordinated with a multivalent metal such as aluminum, iron, copper, zinc, tin, titanium, nickel, antimony, magnesium, vanadium, chromium, and zirconium. have. A mixture of two or more metal chelate compounds may also be used.

Among them, isocyanate-based compounds, especially xylylene diisocyanate, tolylene diisocyanate or hexamethylene diisocyanate; adducts obtained by reacting these isocyanate compounds with polyols such as glycerol or trimethylolpropane; Dimers, trimers, etc. of these isocyanate compounds, or mixtures thereof; A mixture of two or more of the above isocyanate compounds is preferably used. As suitable isocyanate compounds, tolylene diisocyanate, an adduct obtained by reacting tolylene diisocyanate with a polyol, a dimer of tolylene diisocyanate and a trimer of tolylene diisocyanate, and also hexamethylene diisocyanate, hexamethylene diisocyanate reacted with a polyol The adduct body, the dimer of hexamethylene diisocyanate, and the trimer of hexamethylene diisocyanate are mentioned.

The crosslinking agent (C) is usually 0.05 to 5 parts by weight, preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the solid content of the (meth)acrylic resin (A) (the sum of these when two or more types are used). are blended When the blending amount of the crosslinking agent (C) is 0.05 part by weight or more, the durability of the pressure-sensitive adhesive layer tends to improve, and when it is 5 parts by weight or less, white streaks are conspicuous when the optical member with the pressure-sensitive adhesive layer is applied to a liquid crystal display device. It tends to go unnoticed.

(4) ionic compounds (D)

The pressure-sensitive adhesive composition may further contain an ionic compound (D) as an antistatic agent for imparting antistatic properties to the pressure-sensitive adhesive layer. The ionic compound (D) is a compound having an inorganic cation or organic cation and an inorganic anion or organic anion.

Examples of inorganic cations include alkali metal ions such as lithium cation [Li ⁺ ], sodium cation [Na ⁺ ], potassium cation [K ⁺ ], beryllium cation [Be ²⁺ ], magnesium cation [Mg ²⁺ ], and calcium cation ^. and alkaline earth metal ions such as [Ca ²⁺ ].

Examples of organic cations include imidazolium cations, pyridinium cations, pyrrolidinium cations, ammonium cations, sulfonium cations, and phosphonium cations.

Among the cationic components described above, the organic cationic component is preferably used because of its excellent compatibility with the pressure-sensitive adhesive composition. Among the organic cation components, pyridinium cations and imidazolium cations are particularly preferably used from the viewpoint of being difficult to charge when peeling off the peeling film provided on the pressure-sensitive adhesive layer.

As inorganic anions, for example, chloride anion [Cl ^- ], bromide anion [Br ^- ], iodide anion [I ^- ], tetrachloroaluminate anion [AlCl ₄ ^- ], heptachlorodialuminate anion [Al ₂ Cl ₇ ^- ], tetrafluoroborate anion [BF ₄ ^- ], hexafluorophosphate anion [PF ₆ ^- ], perchlorate anion [ClO ₄ ^- ], nitrate anion [NO ₃ -], hexafluoroacenate anion [ AsF ₆ ^- ], hexafluoroantimonate anion [SbF ₆ ^- ], hexafluoroniobate anion [NbF ₆ ^- ], hexafluorotantalate anion [TaF ₆ ^- ], dicyanamide anion [(CN) ₂ N ^- ] etc. are mentioned.

As the organic anion, for example, acetate anion [CH ₃ COO ^- ], trifluoroacetate anion [CF ₃ COO ^- ], methanesulfonate anion [CH ₃ SO ₃ ^- ], trifluoromethanesulfonate anion [CF ₃ SO ₃ ^- ], p-toluenesulfonate anion [p-CH ₃ C ₆ H ₄ SO ₃ ^- ], bis(fluorosulfonyl)imide anion [(FSO ₂ ) ₂ N ^- ], bis(trifluoromethane Sulfonyl)imide anion [(CF ₃ SO ₂ ) ₂ N ^- ], tris(trifluoromethanesulfonyl)methanide anion [(CF ₃ SO ₂ ) ₃ C ^- ], dimethylphosphinate anion [(CH ₃ ) ₂ POO ^- ], (poly) hydrofluorofluoride anion [F(HF) _n ^- ] (n is about 1 to 3), thiocyanate anion [SCN ^- ], perfluorobutanesulfonate anion [C4F ₉ SO ₃ ^- ], bis(pentafluoroethanesulfonyl)imide anion [(C ₂ F ₅ SO ₂ ) ₂ N ^- ], pafluorobutanoate anion [C ₃ F ₇ COO ^- ], (tri Fluoromethanesulfonyl)(trifluoromethanecarbonyl)imide anion [(CF ₃ SO ₂ )(CF ₃ CO)N ^- ], parfluoropropane-1,3-disulfonate anion [ ^- O ₃ S(CF ₂ ) ₃ SO ₃ ^- ], carbonate anion [CO ₃ ^2- ], and the like.

Among the anion components described above, an anion component containing a fluorine atom is preferably used because it gives the ionic compound (D) excellent in antistatic performance. Specifically, a bis(fluorosulfonyl)imide anion, a hexafluorophosphate anion, or a bis(trifluoromethanesulfonyl)imide anion is exemplified.

Specific examples of the ionic compound (D) can be appropriately selected from a combination of the above cationic component and anionic component. When examples of the ionic compound (D) having an organic cation are classified and posted for each structure of the organic cation, the following are exemplified.

Pyridinium salts:

N-hexylpyridinium hexafluorophosphate,

N-octylpyridinium hexafluorophosphate,

N-octyl-4-methylpyridinium hexafluorophosphate,

N-butyl-4-methylpyridinium hexafluorophosphate,

N-decylpyridinium bis(fluorosulfonyl)imide;

N-dodecylpyridinium bis(fluorosulfonyl)imide;

N-tetradecylpyridinium bis(fluorosulfonyl)imide;

N-hexadecylpyridinium bis(fluorosulfonyl)imide,

N-dodecyl-4-methylpyridinium bis(fluorosulfonyl)imide;

N-tetradecyl-4-methylpyridinium bis(fluorosulfonyl)imide;

N-hexadecyl-4-methylpyridinium bis(fluorosulfonyl)imide;

N-benzyl-2-methylpyridinium bis(fluorosulfonyl)imide;

N-benzyl-4-methylpyridinium bis(fluorosulfonyl)imide;

N-hexylpyridinium bis(trifluoromethanesulfonyl)imide,

N-octylpyridinium bis(trifluoromethanesulfonyl)imide,

N-octyl-4-methylpyridinium bis(trifluoromethanesulfonyl)imide;

N-butyl-4-methylpyridinium bis(trifluoromethanesulfonyl)imide.

Imidazolium salts:

1-ethyl-3-methylimidazolium hexafluorophosphate;

1-ethyl-3-methylimidazolium p-toluenesulfonate;

1-ethyl-3-methylimidazolium bis(fluorosulfonyl)imide;

1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide;

1-butyl-3-methylimidazolium methanesulfonate;

1-Butyl-3-methylimidazolium bis(fluorosulfonyl)imide.

Pyrrolidinium salts:

N-butyl-N-methylpyrrolidinium hexafluorophosphate;

N-butyl-N-methylpyrrolidinium bis(fluorosulfonyl)imide;

N-butyl-N-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide.

Quaternary ammonium salts:

tetrabutylammonium hexafluorophosphate;

tetrabutylammonium p-toluenesulfonate;

(2-hydroxyethyl)trimethylammonium bis(trifluoromethanesulfonyl)imide;

(2-hydroxyethyl)trimethylammonium dimethylphosphinate.

In addition, examples of the ionic compound (D) having an inorganic cation include the following.

lithium bromide,

lithium iodide,

lithium tetrafluoroborate;

lithium hexafluorophosphate;

lithium thiocyanate,

lithium perchlorate,

lithium trifluoromethanesulfonate;

Lithium bis(fluorosulfonyl)imide

lithium bis(trifluoromethanesulfonyl)imide;

lithium bis(pentafluoroethanesulfonyl)imide;

lithium tris(trifluoromethanesulfonyl)methanide;

lithium p-toluenesulfonate;

sodium hexafluorophosphate,

sodium bis(fluorosulfonyl)imide;

sodium bis(trifluoromethanesulfonyl)imide;

sodium p-toluenesulfonate,

potassium hexafluorophosphate,

potassium bis(fluorosulfonyl)imide;

potassium bis(trifluoromethanesulfonyl)imide;

Potassium p-toluenesulfonate.

The ionic compound (D) is preferably a solid at room temperature. Compared to the case of using the ionic compound (D), which is liquid at room temperature, antistatic performance can be maintained for a long period of time. From the standpoint of such antistatic long-term stability, the ionic compound (D) preferably has a melting point of 30°C or higher, and more preferably 35°C or higher. On the other hand, if the melting point is too high, the compatibility with the (meth)acrylic resin (A) deteriorates, so the melting point is preferably 90°C or less, more preferably 70°C or less, still more preferably less than 50°C.

The content of the ionic compound (D) in the pressure-sensitive adhesive composition is preferably 0.2 to 8 parts by weight with respect to 100 parts by weight of the solid content of the (meth)acrylic resin (A) (the sum of these when two or more types are used). , more preferably 0.2 to 5 parts by weight, still more preferably 0.3 to 5 parts by weight, particularly preferably 0.5 to 3 parts by weight. When the content of the ionic compound (D) is 0.2 parts by weight or more, it is advantageous to improve the antistatic performance, and when it is 8 parts by weight or less, it is advantageous to improve the durability of the pressure-sensitive adhesive layer.

(5) Silane compound (E)

The pressure-sensitive adhesive composition may further contain a silane compound (E) in order to improve adhesion between the pressure-sensitive adhesive layer and the glass substrate when the pressure-sensitive adhesive layer is bonded to the glass substrate. The silane compound (E) may be contained in the (meth)acrylic resin (A) before blending the crosslinking agent (C).

Examples of the silane compound (E) include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris(2-methoxyethoxy)silane, and N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane. , N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-chloropropylmethyldimethoxysilane, 3-chloropropyltrimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3- Mercaptopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropyldimethoxymethylsilane, 3-glycidoxypropylethoxydimethyl Silane etc. are mentioned. You may use 2 or more types of silane compounds.

The silane compound (E) may be of a silicone oligomer type. Examples of silicone oligomers in the form of (monomer) oligomers include the following.

3-mercaptopropyltrimethoxysilane-tetramethoxysilane copolymer;

3-mercaptopropyltrimethoxysilane-tetraethoxysilane copolymer;

3-mercaptopropyltriethoxysilane-tetramethoxysilane copolymer;

mercaptopropyl group-containing copolymers such as 3-mercaptopropyltriethoxysilane-tetraethoxysilane copolymer;

mercaptomethyltrimethoxysilane-tetramethoxysilane copolymer;

mercaptomethyltrimethoxysilane-tetraethoxysilane copolymer;

mercaptomethyltriethoxysilane-tetramethoxysilane copolymer;

mercaptomethyl group-containing copolymers such as mercaptomethyltriethoxysilane-tetraethoxysilane copolymer;

3-glycidoxypropyltrimethoxysilane-tetramethoxysilane copolymer;

3-glycidoxypropyltrimethoxysilane-tetraethoxysilane copolymer;

3-glycidoxypropyltriethoxysilane-tetramethoxysilane copolymer;

3-glycidoxypropyltriethoxysilane-tetraethoxysilane copolymer;

3-glycidoxypropylmethyldimethoxysilane-tetramethoxysilane copolymer;

3-glycidoxypropylmethyldimethoxysilane-tetraethoxysilane copolymer;

3-glycidoxypropylmethyldiethoxysilane-tetramethoxysilane copolymer;

3-glycidoxypropyl group-containing copolymers such as 3-glycidoxypropylmethyldiethoxysilane-tetraethoxysilane copolymer;

3-methacryloyloxypropyltrimethoxysilane-tetramethoxysilane copolymer;

3-methacryloyloxypropyltrimethoxysilane-tetraethoxysilane copolymer;

3-methacryloyloxypropyltriethoxysilane-tetramethoxysilane copolymer;

3-methacryloyloxypropyltriethoxysilane-tetraethoxysilane copolymer;

3-methacryloyloxypropylmethyldimethoxysilane-tetramethoxysilane copolymer;

3-methacryloyloxypropylmethyldimethoxysilane-tetraethoxysilane copolymer;

3-methacryloyloxypropylmethyldiethoxysilane-tetramethoxysilane copolymer;

copolymers containing a methacryloyloxypropyl group such as 3-methacryloyloxypropylmethyldiethoxysilane-tetraethoxysilane copolymer;

3-acryloyloxypropyltrimethoxysilane-tetramethoxysilane copolymer;

3-acryloyloxypropyltrimethoxysilane-tetraethoxysilane copolymer;

3-acryloyloxypropyltriethoxysilane-tetramethoxysilane copolymer;

3-acryloyloxypropyltriethoxysilane-tetraethoxysilane copolymer;

3-acryloyloxypropylmethyldimethoxysilane-tetramethoxysilane copolymer;

3-acryloyloxypropylmethyldimethoxysilane-tetraethoxysilane copolymer;

3-acryloyloxypropylmethyldiethoxysilane-tetramethoxysilane copolymer;

copolymers containing an acryloyloxypropyl group such as 3-acryloyloxypropylmethyldiethoxysilane-tetraethoxysilane copolymer;

vinyltrimethoxysilane-tetramethoxysilane copolymer,

vinyltrimethoxysilane-tetraethoxysilane copolymer,

vinyltriethoxysilane-tetramethoxysilane copolymer,

vinyltriethoxysilane-tetraethoxysilane copolymer,

vinylmethyldimethoxysilane-tetramethoxysilane copolymer;

vinylmethyldimethoxysilane-tetraethoxysilane copolymer;

vinylmethyldiethoxysilane-tetramethoxysilane copolymer;

vinyl group-containing copolymers such as vinylmethyldiethoxysilane-tetraethoxysilane copolymer;

3-aminopropyltrimethoxysilane-tetramethoxysilane copolymer;

3-aminopropyltrimethoxysilane-tetraethoxysilane copolymer;

3-aminopropyltriethoxysilane-tetramethoxysilane copolymer;

3-aminopropyltriethoxysilane-tetraethoxysilane copolymer;

3-aminopropylmethyldimethoxysilane-tetramethoxysilane copolymer;

3-aminopropylmethyldimethoxysilane-tetraethoxysilane copolymer;

3-aminopropylmethyldiethoxysilane-tetramethoxysilane copolymer;

amino group-containing copolymers such as 3-aminopropylmethyldiethoxysilane-tetraethoxysilane copolymer;

Most of the silane compounds (E) exemplified above are liquids. The content of the silane compound (E) in the pressure-sensitive adhesive composition is 0.01 to 10 parts by weight relative to 100 parts by weight of the solid content of the (meth)acrylic resin (A) (the sum of these when two or more types are used), preferably. is 0.05 to 5 parts by weight, more preferably 0.2 to 0.4 parts by weight. When the amount of the silane compound (E) is 0.01 parts by weight or more, the effect of improving the adhesion between the pressure-sensitive adhesive layer and the glass substrate is easily obtained. Moreover, if the content is 10 parts by weight or less, the bleed-out of the silane compound (E) from the pressure-sensitive adhesive layer can be suppressed.

(6) Other ingredients

The pressure-sensitive adhesive composition may contain additives such as a crosslinking catalyst, a weathering stabilizer, a tackifier, a plasticizer, a softener, a dye, a pigment, an inorganic filler, light-scattering fine particles, and a resin other than the (meth)acrylic resin (A). . In addition, it is also useful to mix an ultraviolet curable compound with an adhesive composition, form an adhesive layer, and then irradiate and cure the adhesive with ultraviolet rays to obtain a harder adhesive layer.

When the pressure-sensitive adhesive composition contains a crosslinking catalyst together with the crosslinking agent (C), the pressure-sensitive adhesive layer can be prepared by aging in a short time. In addition, when a crosslinking catalyst is incorporated, floating or peeling at the interface between the pressure-sensitive adhesive layer and a member adjacent thereto and foaming of the pressure-sensitive adhesive layer can be more effectively suppressed, and the reworkability can also be further improved in some cases. Examples of the crosslinking catalyst include amine compounds such as hexamethylenediamine, ethylenediamine, polyethyleneimine, hexamethylenetetramine, diethylenetriamine, triethylenetetramine, isophoronediamine, trimethylenediamine, polyamino resin and melamine resin. can be heard When blending an amine-based compound as a cross-linking catalyst in the pressure-sensitive adhesive composition, an isocyanate-based compound is suitable as the cross-linking agent (C).

The pressure-sensitive adhesive composition usually does not substantially contain a polymerization initiator. The content of the polymerization initiator in the pressure-sensitive adhesive composition is preferably 0.01 part by weight or less, and ideally 0 part by weight, based on 100 parts by weight of the pressure-sensitive adhesive composition. Examples of the polymerization initiator include a photopolymerization initiator that self-decomposes to generate radicals when irradiated with light, and a thermal polymerization initiator that self-decomposes to generate radicals when heated.

The adhesive composition of the present invention contains compound (B) so as not to react with other components in the adhesive composition. For this reason, the pressure-sensitive adhesive composition of the present invention can achieve both high durability and reworkability.

<Adhesive layer>

The pressure-sensitive adhesive layer according to the present invention contains the above-described pressure-sensitive adhesive composition according to the present invention, and typically consists of the pressure-sensitive adhesive composition according to the present invention. The pressure-sensitive adhesive layer can be obtained by dissolving or dispersing each component constituting the pressure-sensitive adhesive composition in a solvent to obtain a solvent-containing pressure-sensitive adhesive composition, then applying onto a base film and drying. The pressure-sensitive adhesive layer according to the present invention is excellent in durability and reworkability, and is also excellent in suppressing the enhancement of peeling force of a peeling film laminated on the surface thereof. Even if a solvent-containing adhesive composition is applied and dried in an environment exposed to light, in a relatively high-temperature environment, or in an oxygen-containing atmosphere, an adhesive layer having higher durability and reworkability can be easily formed. It is preferable that the double bond of the compound (B) contained in the composition is a double bond contained in a methacryloyl group.

It is common that the base film is a plastic film, and a release film (separator) subjected to release treatment is exemplified as a typical example thereof. The peeling film may be, for example, a film made of various resins such as polyethylene terephthalate, polybutylene terephthalate, polycarbonate, and polyarylate, to which a release treatment such as silicone treatment is applied to the surface on which the pressure-sensitive adhesive layer is formed. . Moreover, it is good also as an optical member with an adhesive layer by apply|coating an adhesive composition directly to the surface of an optical member, forming an adhesive layer, and laminating a peeling film on the outer surface of the adhesive layer as needed. When providing the pressure-sensitive adhesive layer on the surface of the optical member, a surface activation treatment such as plasma treatment, corona treatment, or the like may be applied to the bonding surface of the optical member and/or the bonding surface of the pressure-sensitive adhesive layer, if necessary.

The thickness of the pressure-sensitive adhesive layer is preferably 10 to 45 μm, more preferably 10 to 30 μm, and still more preferably 10 to 20 μm. When the thickness of the pressure-sensitive adhesive layer is 45 μm or less, the adhesiveness in a high-temperature, high-humidity environment is improved, and the possibility of floating or peeling between the pressure-sensitive adhesive layer and the member (eg glass substrate) to which the pressure-sensitive adhesive layer is bonded tends to decrease, and further There is a tendency for reworkability to be improved. Moreover, if the thickness is 10 μm or more, when the optical member with an adhesive layer is applied to a liquid crystal display device, even if the dimensions of the optical member change, since the adhesive layer follows the dimensional change and fluctuates, the brightness of the periphery of the liquid crystal cell and There is no difference between center brightness, so white streaks and color unevenness tend to be suppressed. Conventionally, in general, the thickness of the pressure-sensitive adhesive layer adhered to the liquid crystal cell was 25 μm as a standard, but in the present invention, even when the thickness is 20 μm or less, sufficient performance as the pressure-sensitive adhesive layer is exhibited.

It is preferable that the adhesive layer has a gel fraction in the range of 30 to 85%. A gel fraction of 30% or more is advantageous for durability under high temperature and high humidity, and also tends to lower the possibility of floating or peeling between the member (eg glass substrate) bonding the pressure-sensitive adhesive layer and the pressure-sensitive adhesive layer, and furthermore, Workability tends to improve. On the other hand, if the gel fraction is 85% or less, when the optical member with an adhesive layer is applied to a liquid crystal display device, even if the dimensions of the optical member change, since the adhesive layer follows the dimensional change and fluctuates, the brightness of the periphery of the liquid crystal cell There is no difference between the brightness of the center and the brightness of the center, so white streaks and color unevenness tend to be suppressed.

ADVANTAGE OF THE INVENTION According to the adhesive composition concerning this invention, in the optical member with an adhesive layer mentioned later provided with the adhesive layer provided with the peeling film (separator) on at least one surface, and the peeling film laminated|stacked on the outer surface of the adhesive layer, 70 degreeC When the peel force of the release film after the heating test maintained for 20 days is P ₁ and the peel force before the heating test is P ₀ , the peel force enhancement rate defined by the following formula is 200% or less, and further 180% or less it is possible:

Peel force enhancement rate (%) = (P ₁ /P ₀ )×100

<Optical member with adhesive layer>

The pressure-sensitive adhesive layer according to the present invention can be suitably used as a pressure-sensitive adhesive layer for bonding members to each other, particularly optical members to each other. The optical member with a pressure-sensitive adhesive layer according to the present invention may be, for example, one in which a pressure-sensitive adhesive layer is laminated on a certain optical member, and another optical member laminated and bonded to the outer surface of the pressure-sensitive adhesive layer.

(1) First embodiment

One preferred embodiment of the optical member with a pressure-sensitive adhesive layer according to the present invention includes a resin film and a pressure-sensitive adhesive layer laminated on at least one surface thereof. The resin film is bonded to an optical film such as a polarizer, a protective film, or a retardation film, or an optical film that is an object to be protected, and a surface protection film used for the purpose of protecting the surface from scratches or dirt.

The polarizer is a film having a function of extracting linearly polarized light from incident natural light, and a suitable example is one in which a dichroic dye such as iodine or dichroic dye is adsorbed and oriented on a uniaxially stretched polyvinyl alcohol-based resin film. The thickness of the polarizer is not particularly limited, but is usually 0.5 to 35 μm.

The protective film may be made of a light-transmitting (preferably optically transparent) resin such as a polyolefin-based resin such as chain polyolefin-based resin (polypropylene-based resin or the like) or cyclic polyolefin-based resin (norbornene-based resin or the like); cellulosic resins such as triacetyl cellulose and diacetyl cellulose; polyester-based resin; polycarbonate-based resin; (meth)acrylic resin; polystyrene-based resin; polyether ether ketone resins; It may be a film made of a thermoplastic resin such as polysulfone resin. The protective film may contain an ultraviolet absorber such as a salicylic acid ester compound, a benzophenone compound, a benzotriazole compound, a triazine compound, a cyanoacrylate compound, or a nickel complex salt compound. The thermoplastic resin constituting the protective film is preferably a cellulose-based resin or a (meth)acrylic-based resin.

Examples of the chain polyolefin resin include homopolymers of chain olefins such as polyethylene resins and polypropylene resins, as well as copolymers composed of two or more types of chain olefins.

Cyclic polyolefin resin is a general term for resins polymerized using cyclic olefins as polymerized units. Specific examples of cyclic polyolefin resins include ring-opening (co)polymers of cyclic olefins, addition polymers of cyclic olefins, copolymers of cyclic olefins and chain olefins such as ethylene and propylene (typically random copolymers), and unsaturated graft polymers modified with carboxylic acids or derivatives thereof, and hydrides thereof. Among them, a norbornene-based resin using a norbornene-based monomer such as norbornene or a polycyclic norbornene-based monomer as the cyclic olefin is preferably used.

The cellulose-based resin is a partial or complete esterified product of cellulose, and examples thereof include cellulose acetate esters, propionic acid esters, butyric acid esters, and mixed esters thereof. Among them, triacetyl cellulose, diacetyl cellulose, cellulose acetate propionate, cellulose acetate butylate and the like are preferably used.

The polyester-based resin is a resin other than the above cellulose-based resin having an ester bond, and is generally composed of a polycondensate of a polyhydric carboxylic acid or a derivative thereof and a polyhydric alcohol. Dicarboxylic acids or derivatives thereof may be used as polyhydric carboxylic acids or derivatives thereof, and examples thereof include terephthalic acid, isophthalic acid, dimethyl terephthalate, and dimethyl naphthalene dicarboxylic acid. As the polyhydric alcohol, diols can be used, and examples thereof include ethylene glycol, propanediol, butanediol, neopentyl glycol, and cyclohexanedimethanol.

Specific examples of the polyester-based resin include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polytrimethylene terephthalate, polytrimethylene naphthalate, polycycle hexane dimethyl terephthalate, and polycyclohexane. Contains dimethylnaphthalate.

A polycarbonate-type resin consists of a polymer to which monomer units are bonded via a carbonate group. The polycarbonate-based resin may be a resin called a modified polycarbonate obtained by modifying a polymer skeleton, a copolymerized polycarbonate, or the like.

The (meth)acrylic resin may be a polymer containing methacrylic acid ester as a main monomer, and is preferably a copolymer in which a small amount of other comonomer components are copolymerized. The (meth)acrylic resin is more preferably a copolymer of methyl methacrylate and methyl acrylate, and a third monofunctional monomer may be further copolymerized.

Examples of the third monofunctional monomer include ethyl methacrylate, butyl methacrylate, cyclohexyl methacrylate, phenyl methacrylate, benzyl methacrylate, 2-ethylhexyl methacrylate, and 2-hydroxy methacrylate. methacrylic acid esters other than methyl methacrylate such as ethyl; acrylic esters other than methyl acrylate, such as ethyl acrylate, butyl acrylate, cyclohexyl acrylate, phenyl acrylate, benzyl acrylate, 2-ethylhexyl acrylate, and 2-hydroxyethyl acrylate; hydroxyalkyl acrylic acid esters such as 2-(hydroxymethyl)methyl acrylate, 2-(1-hydroxyethyl)methyl acrylate, 2-(hydroxymethyl)ethyl acrylate, and 2-(hydroxymethyl)butyl acrylate; unsaturated acids such as methacrylic acid and acrylic acid; halogenated styrenes such as chlorostyrene and bromostyrene; substituted styrenes such as vinyltoluene and α-methylstyrene; unsaturated nitriles such as acrylonitrile and methacrylonitrile; unsaturated acid anhydrides such as maleic anhydride and citraconic anhydride; and unsaturated imides such as phenyl maleimide and cyclohexyl maleimide. The third monofunctional monomer may be used alone or in combination of two or more.

You may further copolymerize a polyfunctional monomer to (meth)acrylic-type resin. Examples of the polyfunctional monomer include ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, and nonaethylene glycol di. (meth)acrylate, ethylene glycol such as tetradecaethylene glycol di(meth)acrylate, or those obtained by esterifying hydroxyl groups at both terminals of oligomers thereof with acrylic acid or methacrylic acid; What esterified the hydroxyl groups of both terminals of propylene glycol or its oligomer with acrylic acid or methacrylic acid; What esterified the hydroxyl group of dihydric alcohols, such as neopentyl glycol di(meth)acrylate, hexanediol di(meth)acrylate, and butanediol di(meth)acrylate, with acrylic acid or methacrylic acid; bisphenol A, alkylene oxide adducts of bisphenol A, or those obtained by esterifying the hydroxyl groups at both terminals of halogen-substituted products thereof with acrylic acid or methacrylic acid; those obtained by esterifying a polyhydric alcohol such as trimethylolpropane or pentaerythritol with acrylic acid or methacrylic acid, and those obtained by ring-opening addition of an epoxy group of glycidyl acrylate or glycidyl methacrylate to these terminal hydroxyl groups; dibasic acids such as succinic acid, adipic acid, terephthalic acid, phthalic acid, halogen-substituted products thereof, and alkylene oxide adducts thereof, etc., with ring-opening addition of an epoxy group of glycidyl acrylate or glycidyl methacrylate; aryl (meth)acrylate; aromatic divinyl compounds such as divinylbenzene; and the like. Especially, ethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, and neopentyl glycol dimethacrylate are used preferably.

The (meth)acrylic resin may be further modified by performing a reaction between the functional groups of the copolymer. As the reaction, for example, a demethanol condensation reaction in a polymer chain between a methyl ester group of methyl acrylate and a hydroxyl group of 2-(hydroxymethyl)methyl acrylate, a carboxyl group of acrylic acid and a hydroxyl group of 2-(hydroxymethyl)methyl acrylate A dehydration condensation reaction in a polymer chain, etc. are mentioned. Further, the (meth)acrylic resin may have any structure of a glutarimide derivative, a glutaric anhydride derivative, or a lactone ring structure.

The glass transition temperature of the (meth)acrylic resin is preferably 90 to 160°C, more preferably 110 to 160°C, still more preferably 120 to 150°C.

The (meth)acrylic resin may contain additives as needed. Examples of additives include lubricants, antiblocking agents, heat stabilizers, antioxidants, antistatic agents, light resistance agents, impact resistance modifiers, and surfactants.

The (meth)acrylic resin may contain acrylic rubber particles as an impact modifier from the viewpoint of the film forming property to the film and the impact resistance of the film. Acrylic rubber particles are particles containing an acrylic acid ester-based elastomer as an essential component, and those having a single-layer structure substantially composed only of this elastomer and those having a multi-layer structure containing this elastomer as one layer are listed. can As an example of this elastic polymer, a crosslinked elastic copolymer obtained by copolymerizing an alkyl acrylate as a main component with another vinyl monomer and a crosslinkable monomer copolymerizable therewith can be given. Examples of the alkyl acrylate serving as the main component of the elastomer include methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate and the like, and those having an alkyl group of about 1 to 8 carbon atoms, particularly acrylic acid having an alkyl group of 4 or more carbon atoms. This is preferably used. Examples of other vinyl monomers copolymerizable with this alkyl acrylate include compounds having one polymerizable carbon-carbon double bond in the molecule, and more specifically, methacrylic acid esters such as methyl methacrylate and styrene. aromatic vinyl compounds and vinyl cyan compounds such as acrylonitrile; and the like. Examples of the crosslinkable monomer include crosslinkable compounds having at least two polymerizable carbon-carbon double bonds in the molecule, and more specifically, ethylene glycol di(meth)acrylate, butanedioldi(meth)acrylate and (meth)acrylates of polyhydric alcohols, alkenyl esters of (meth)acrylic acid such as allyl (meth)acrylates, and divinylbenzene.

A laminate of a film made of (meth)acrylic resin containing no rubber particles and a film made of (meth)acrylic resin containing rubber particles can also be used as a protective film.

The retardation film is an optical film exhibiting optical anisotropy, and includes, for example, polyvinyl alcohol-based resins, polyarylate-based resins, polyimide-based resins, polyethersulfone-based resins, and polyvinylidene fluorocarbons in addition to resins usable for the protective film. It may be a stretched film obtained by stretching a resin film made of fluoride/polymethyl methacrylate-based resin, liquid crystal polyester-based resin, ethylene-vinyl acetate copolymer saponified product, polyvinyl chloride-based resin or the like by about 1.01 to 6 times. Among them, a stretched film obtained by uniaxially stretching or biaxially stretching a polycarbonate-based resin film, a cyclic polyolefin-based resin film, a (meth)acrylic-based resin film, or a cellulose-based resin film is preferable. In this specification, a zero retardation film is also included in the retardation film (however, the zero retardation film can also be used as a protective film). In addition, films called uniaxial retardation film, wide viewing angle retardation film, low-elasticity retardation film, etc. can also be applied as the retardation film.

The zero retardation film refers to a film in which both the in-plane retardation value R _e and the thickness direction retardation value R _th are -15 to 15 nm. This retardation film is suitably used for an IPS mode liquid crystal display device. The in-plane retardation value R _e and the thickness direction retardation value R _th are preferably both -10 to 10 nm, more preferably -5 to 5 nm together. The in-plane retardation value R _e and the thickness direction retardation value R _th referred to herein are values at a wavelength of 590 nm.

The in-plane retardation value R _e and the thickness direction retardation value R _th are each defined by the following formula:

R _e = (n _x -n _y )×d

R _th =[(n _x +n _y )/2-n _z ]×d.

In the formula, n _x is the refractive index in the film in-plane slow axis direction (x-axis direction), n _y is the refractive index in the film in-plane fast axis direction (y-axis direction orthogonal to the x-axis in-plane), and n _z is the film thickness is the refractive index in the direction (the z-axis direction perpendicular to the film plane), and d is the thickness of the film.

For the zero retardation film, for example, a resin film made of polyolefin resins such as cellulose resins, chain polyolefin resins and cyclic polyolefin resins, polyethylene terephthalate resins, or (meth)acrylic resins can be used. In particular, cellulose-based resins, polyolefin-based resins, or (meth)acrylic-based resins are preferably used because the control of the retardation value is easy and the acquisition is easy. For example, a retardation film obtained by laminating a (meth)acrylic resin layer on one or both surfaces of a retardation developing layer made of a resin different from the (meth)acrylic resin may be used.

When a pressure-sensitive adhesive layer is laminated on an optical film such as a retardation film or a protective film and bonded to a glass substrate or the like through the pressure-sensitive adhesive layer, if the moisture permeability of the optical film is low, it becomes difficult for moisture in the pressure-sensitive adhesive layer to escape. Due to this, there are many cases where, for example, foaming occurs, which is disadvantageous in terms of durability, particularly under high-temperature conditions. In contrast, in the optical member with a pressure-sensitive adhesive layer according to the present invention, when the optical film is used as the optical member, the optical film is measured at a temperature of 40°C and a relative humidity of 90% by the cup method specified in JIS Z 0208. Even when the moisture permeability is as low as 300 g/(m 2 24 hr) or less, excellent durability can be exhibited. As an example of an optical film with low water vapor transmission rate, the above cyclic polyolefin type resin film and (meth)acrylic type resin film are mentioned.

In addition, a film in which optical anisotropy is expressed by application/orientation of a liquid crystalline compound or a film in which optical anisotropy is expressed by application of an inorganic layered compound can also be used as a retardation film. Such retardation films include what is called a temperature-compensated retardation film, a film in which rod-shaped liquid crystals are obliquely aligned and sold under the trade name "NH film" by JX Nikko Nisseki Energy Co., Ltd., and Fujifilm Co., Ltd. A film in which disk-shaped liquid crystals are tilt-oriented, sold under the trade name “WV film”, and a completely biaxially oriented film sold under the trade name “VAC film” by Sumitomo Chemical Co., Ltd., similarly produced by Sumitomo Chemical Co., Ltd. There is a biaxially oriented film and the like sold under the trade name of "new VAC film".

On the other hand, the surface protection film is a film used for the purpose of protecting the surface of an optical film or the like, which is an object to be protected, from scratches and dirt. , Various types of optical films such as reflective sheets are usually circulated in a state where a surface protection film is bonded to the surface (in the case of having an adhesive layer on one side, the surface opposite to the adhesive layer). As for the surface protection film, after bonding the said optical film together to a liquid crystal cell etc., peeling removal is common practice.

As a base material of the surface protection film, for example, polyolefin-based resins such as polyethylene, polypropylene, and polymethylpentene; fluorinated polyolefin-based resins such as polyvinyl fluoride, polyvinylidene fluoride, and polyethylene fluoride; polyester resins such as polyethylene naphthalate, polyethylene terephthalate, polybutylene terephthalate, and polyethylene terephthalate/isophthalate copolymer; polyamides such as nylon 6 and nylon 6,6; vinyl polymers such as polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, polyvinyl alcohol, and vinylon; cellulosic resins such as triacetyl cellulose, diacetyl cellulose, and cellophane; (meth)acrylic resins such as polymethyl methacrylate, polyethyl methacrylate, polyethyl acrylate, and polybutyl acrylate; Others include films made of thermoplastic resins such as polystyrene, polycarbonate, polyarylate, and polyimide. The optical member with an adhesive layer according to the present invention, wherein the resin film is a surface protection film, has an adhesive layer provided on the substrate.

In the optical member with a pressure-sensitive adhesive layer according to the present embodiment, it is preferable to adhere the above-mentioned peeling film to the surface of the pressure-sensitive adhesive layer, and to temporarily adhere and protect until use. The optical member with a pressure-sensitive adhesive layer according to the present embodiment to which a release film is adhered includes a method in which an adhesive composition is applied on a release film to form an adhesive layer, and a resin film is further laminated on the obtained adhesive layer, and the adhesive composition is applied on the resin film. It can manufacture by the method of apply|coating to form the adhesive layer, and bonding a peeling film to the adhesive surface.

(2) Second Embodiment

Another preferred embodiment of the optical member with a pressure-sensitive adhesive layer according to the present invention includes a laminate of resin films and a pressure-sensitive adhesive layer laminated on at least one surface thereof. It is preferable that the laminate of resin films is a laminate of optical films selected from optical films, such as a polarizer, a protective film, and retardation film. A representative example of a laminate of optical films is a polarizing plate. Also in the optical member with the pressure-sensitive adhesive layer according to the present embodiment, it is preferable to adhere a release film to the surface of the pressure-sensitive adhesive layer to temporarily adhere and protect until use.

As the polarizing plate, a linear polarizing plate having a property of absorbing linearly polarized light having a vibrating plane in any direction incident on the film plane and transmitting linearly polarized light having a vibrating plane orthogonal thereto, and a linear polarizing plate having a vibrating plane in any direction incident on the film plane A polarization separator having a property of reflecting polarized light and transmitting linearly polarized light having a plane of vibration orthogonal thereto, an elliptically polarizing plate obtained by laminating a retardation film on a linear polarizing plate, and the like.

A linear polarizing plate generally has a structure in which the above-mentioned protective film is bonded to one side or both sides of the above-mentioned polarizer. When a protective film is bonded on both surfaces of a polarizer, an adhesive layer is formed in the at least one surface of the protective film. When bonding a protective film only on one surface of a polarizer, an adhesive layer can be formed in the surface (surface to which a protective film is not bonded) of a polarizer. An elliptically polarizing plate is obtained by laminating a retardation film on a linear polarizing plate, and the linear polarizing plate generally has the same configuration as above. When the pressure-sensitive adhesive layer is laminated on the elliptically polarizing plate, the pressure-sensitive adhesive layer is usually laminated on the retardation film side.

A specific example of an optical member with an adhesive layer in a case where the optical member is a polarizing plate will be described with reference to the drawings. In the example shown in FIG. 1, a protective film 3 having a surface treatment layer 2 is adhered to one surface of a polarizer 1 on the surface opposite to the surface treatment layer 2, and a polarizing plate 10 is formed. This consists of The adhesive layer 20 is provided on the surface of the polarizer 1 opposite to the protective film 3, and the polarizing plate with an adhesive layer (optical member with an adhesive layer) 25 is comprised. This pressure-sensitive adhesive layer 20 can be bonded to the glass substrate 30 from the surface opposite to the polarizing plate 10, but the glass substrate 30 will be described later.

In the example shown in FIG. 2, the 1st protective film 3 which has the surface treatment layer 2 is stuck to one surface of the polarizer 1 from the surface opposite to the surface treatment layer 2, and the polarizer The second protective film 4 is adhered to the other surface of (1) to form the polarizing plate 10. The adhesive layer 20 is provided on the outer surface of the 2nd protective film 4, and the polarizing plate 25 with an adhesive layer is comprised.

In the example shown in FIG. 3 , a protective film 3 having a surface treatment layer 2 is adhered to one surface of a polarizer 1 on the surface opposite to the surface treatment layer 2, and the polarizer 1 ), the polarizing plate 10 is configured by attaching the retardation film 7 via the interlayer adhesive 8 to the other side of the ). An adhesive layer 20 is provided on the outer surface of the retardation film 7 to form a polarizing plate 25 with an adhesive layer.

In the example shown in FIG. 4, the 1st protective film 3 which has the surface treatment layer 2 is stuck to one side of the polarizer 1 from the surface opposite to the surface treatment layer 2, and the polarizer The second protective film 4 is adhered to the other surface of (1), and the retardation film 7 is adhered to the outer surface via an interlayer adhesive 8 to form the polarizing plate 10. An adhesive layer 20 is provided on the outer surface of the retardation film 7 to form a polarizing plate 25 with an adhesive layer.

The surface treatment layer 2 formed on the surface of the protective film 3 may be a hard coat layer, an antiglare layer, an antireflection layer, an antistatic layer, or the like. A plurality of layers may be provided among these.

As in the examples shown in FIGS. 3 and 4 , when the polarizing plate 10 includes the retardation film 7 , as a suitable example of the retardation film 7 in the case of a small and medium-sized liquid crystal display device, a 1/4 wave plate is used. can be cited as an example. In this case, it is common to place the absorption axis of the polarizer 1 and the slow axis of the retardation film 7 at approximately 45 degrees, but depending on the characteristics of the liquid crystal cell, the angle may be shifted from 45 degrees to some extent. have. On the other hand, in the case of a large liquid crystal display device such as a television, a retardation film 7 having various retardation values according to the characteristics of the liquid crystal cell is used for the purpose of compensating for the retardation or viewing angle of the liquid crystal cell. In this case, it is common to arrange so that the absorption axis of polarizer 1 and the slow axis of retardation film 7 may be substantially orthogonal or substantially parallel. When the retardation film 7 is constituted by a 1/4 wave plate, a uniaxially or biaxially stretched film is suitably used. Further, when the retardation film 7 is installed for the purpose of retardation compensation or viewing angle compensation of a liquid crystal cell, liquid crystal on a film or support film oriented in the thickness direction in addition to uniaxial or biaxially stretched film in addition to uniaxial or biaxially stretched film. As the retardation film 7, what is called an optical compensation film, such as a film obtained by applying a retardation developing material such as the like, and orientation-fixed thereto, can also be used.

It is common practice to use a general (meth)acrylic pressure-sensitive adhesive for the interlayer pressure-sensitive adhesive 8 in FIGS. 3 and 4, but it is also possible to use the pressure-sensitive adhesive layer according to the present invention. In the case of arranging such that the absorption axis of the polarizer 1 and the slow axis of the retardation film 7 are substantially orthogonal or substantially parallel to each other, such as in the aforementioned large-size liquid crystal display device, an adhesive is used instead of the interlayer adhesive 8. can also be used Examples of the adhesive include water-based adhesives composed of an aqueous solution or aqueous dispersion and exhibiting adhesive strength by evaporating water as a solvent, and ultraviolet curable adhesives that exhibit adhesive strength by being cured by ultraviolet irradiation. Bonding between the polarizer 1 and the protective films 3 and 4 is also usually performed using an adhesive.

(3) Third Embodiment

Another preferable embodiment of the optical member with an adhesive layer according to the present invention is that another optical member is laminated and bonded to the outer surface of the adhesive layer in the optical member with an adhesive layer according to the first or second embodiment. The other optical member is preferably a glass substrate, and FIGS. 1 to 4 show bonding of the polarizing plate with an adhesive layer according to the second embodiment to the glass substrate 30 .

As the glass substrate 30, a glass substrate of a liquid crystal cell, glass for antiglare, glass for sunglasses, etc. are mentioned, for example. As a material of the glass substrate 30, soda-lime glass, low-alkali glass, non-alkali glass etc. are mentioned, for example. Especially, it is preferable that a glass substrate is a glass substrate of a liquid crystal cell.

A liquid crystal cell is usually laminated with polarizing plates via pressure-sensitive adhesive layers on both sides of the cell. Among these polarizing plates, only the polarizing plate disposed on the front side (visible side) of the liquid crystal cell may be the polarizing plate with the pressure-sensitive adhesive layer according to the present invention, and the back side of the liquid crystal cell Only the polarizing plate disposed on the side (backlight side) may be the polarizing plate with the pressure-sensitive adhesive layer according to the present invention, or both may be the polarizing plate with the pressure-sensitive adhesive layer according to the present invention. The driving system of the liquid crystal cell may be any conventionally known system. A polarizing plate placed on the rear side (backlight side) usually does not have the surface treatment layer 2 . Various optical films known to be disposed on the rear side of the liquid crystal cell, such as a brightness enhancing film, a condensing film, and a diffusion film, may be provided on the outer surface of the polarizing plate disposed on the rear side.

Optical members with an adhesive layer, such as a polarizing plate with an adhesive layer, can be used suitably for a liquid crystal display device. Liquid crystal display devices include, for example, personal computers including notebook type, desktop type, PDA (Personal Digital Assistant) and the like; various mobile devices such as smart phones and tablet terminals; television; vehicle-mounted displays; Electronic Dictionary; digital camera; digital video camera; electronic desk calculator; It can be suitably used as a liquid crystal display device for watches and the like.

Example

Hereinafter, the present invention will be described in more detail by describing examples and comparative examples, but the present invention is not limited by these examples. Hereinafter, the parts and percentages used to indicate the amount used or the content are based on weight unless otherwise specified.

In the following examples, the weight average molecular weight (Mw) and number average molecular weight (Mn) of the (meth)acrylic resin were measured using four "TSKgel XL" manufactured by Tosoh Corporation as a column in a GPC apparatus and Showa Denko ( Note) A total of five "Shodex GPC KF-802" manufactured and sold by Shokotsusho Co., Ltd. were placed in series, and tetrahydrofuran was used as an eluent at a sample concentration of 5 mg/mL and a sample introduction amount. It was measured by standard polystyrene conversion under conditions of 100 µL, temperature of 40°C, and flow rate of 1 mL/min.

<Preparation Example 1: Preparation of (meth)acrylic resin 1 for pressure-sensitive adhesive layer>

120 parts of ethyl acetate was placed in a reaction vessel equipped with a cooling tube, a nitrogen inlet tube, a thermometer and a stirrer, and the air in the apparatus was substituted with nitrogen gas to make it free of oxygen, and then the internal temperature was raised to 75°C. After adding the entire solution of 0.05 parts of azobisisobutyronitrile (polymerization initiator) in 5 parts of ethyl acetate, while maintaining the internal temperature at 74-76 ° C., 65.7 parts of butyl acrylate, 30.0 parts of methyl acrylate, 2-hydroxy acrylate A mixed solution of 4.0 parts of oxyethyl and 0.3 part of 2-carboxyethyl acrylate was added dropwise into the reaction system over 2 hours. Further, the reaction was completed by keeping the mixture warm at an internal temperature of 74 to 76°C for 5 hours. Finally, ethyl acetate was added and the concentration of the (meth)acrylic resin was adjusted to 40% to prepare an ethyl acetate solution of the (meth)acrylic resin 1. The obtained (meth)acrylic resin 1 had a weight average molecular weight (Mw) of 680,000 and Mw/Mn of 4.9.

<Preparation Example 2: Preparation of (meth)acrylic resin 2 for pressure-sensitive adhesive layer>

120 parts of ethyl acetate was placed in a reaction vessel equipped with a cooling tube, a nitrogen inlet tube, a thermometer and a stirrer, and the air in the apparatus was substituted with nitrogen gas to make it free of oxygen, and then the internal temperature was raised to 75°C. After adding the entire solution of 0.05 parts of azobisisobutyronitrile (polymerization initiator) in 5 parts of ethyl acetate, while maintaining the internal temperature at 74-76 ° C., 50.7 parts of butyl acrylate, 45.0 parts of methyl acrylate, 2-hydroxy acrylate A mixed solution of 4.0 parts of oxyethyl and 0.3 part of 2-carboxyethyl acrylate was added dropwise into the reaction system over 2 hours. Further, the reaction was completed by keeping the mixture warm at an internal temperature of 74 to 76°C for 5 hours. Finally, ethyl acetate was added and the concentration of the (meth)acrylic resin was adjusted to 40% to prepare an ethyl acetate solution of the (meth)acrylic resin 2. The obtained (meth)acrylic resin 2 had a weight average molecular weight (Mw) of 650,000 and Mw/Mn of 4.2.

<Preparation Example 3: Preparation of (meth)acrylic resin 3 for pressure-sensitive adhesive layer>

A mixed solution of 81.8 parts of ethyl acetate, 72.2 parts of butyl acrylate, 20.0 parts of methyl acrylate, 6.0 parts of 2-hydroxyethyl acrylate and 1.8 parts of acrylic acid was placed in a reaction vessel equipped with a cooling pipe, nitrogen inlet pipe, thermometer and stirrer, and nitrogen gas was added. The air in the furnace was substituted and the internal temperature was raised to 55°C while making it free of oxygen. Thereafter, a solution obtained by dissolving 0.14 parts of azobisisobutyronitrile (polymerization initiator) in 10 parts of ethyl acetate was added in its entirety. One hour after the addition of the initiator, ethyl acetate was continuously added into the reaction vessel at an addition rate of 17.3 parts/hr so that the concentration of the (meth)acrylic resin was 35%, and kept warm at an internal temperature of 54 to 56° C. for 12 hours, and finally Ethyl acetate was added thereto and the concentration of (meth)acrylic resin was adjusted to 20% to obtain a solution of (meth)acrylic resin 3. The obtained (meth)acrylic resin 3 had a weight average molecular weight (Mw) of 1,440,000 and a molecular weight distribution (Mw/Mn) of 4.6.

<Preparation Example 4: Preparation of (meth)acrylic resin 4 for pressure-sensitive adhesive layer>

Into a reaction vessel equipped with a cooling tube, a nitrogen inlet tube, a thermometer and a stirrer, a mixed solution of 81.8 parts of ethyl acetate, 91.0 parts of butyl acrylate, 5.0 parts of methyl acrylate, 4.0 parts of 2-hydroxyethyl acrylate and 0.3 part of 2-carboxyethyl acrylate was charged. Then, the air in the apparatus was substituted with nitrogen gas to raise the internal temperature to 55°C while making it free of oxygen. Thereafter, a solution obtained by dissolving 0.14 parts of azobisisobutyronitrile (polymerization initiator) in 10 parts of ethyl acetate was added in its entirety. One hour after the addition of the initiator, ethyl acetate was continuously added into the reaction vessel at an addition rate of 17.3 parts/hr so that the concentration of the (meth)acrylic resin was 35%, and kept warm at an internal temperature of 54 to 56° C. for 12 hours, and finally Ethyl acetate was added thereto and the concentration of (meth)acrylic resin was adjusted to 20% to obtain a solution of (meth)acrylic resin 4. The obtained (meth)acrylic resin 4 had a weight average molecular weight (Mw) of 1,440,000 and a molecular weight distribution (Mw/Mn) of 4.6.

On the other hand, when the amount of each monomer used in the production of (meth)acrylic resin 4 obtained above is converted per 100 parts by weight of the total amount, it is as follows:

90.7 parts of butyl acrylate,

5.0 parts of methyl acrylate,

4.0 parts of 2-hydroxyethyl acrylate, and

0.3 parts of 2-carboxyethyl acrylate.

<Examples 1 to 10, Comparative Examples 1 to 5>

(1) Preparation of pressure-sensitive adhesive composition

With respect to 100 parts of the solid content of the (meth)acrylic resin (A) obtained in Production Examples 1 to 4, the compound (B), crosslinking agent (C), ionic compound (D) and silane compound (E) shown in Table 2 were mixed in the amounts shown in Table 2, and in the case of using (meth)acrylic resin 1 or 2, the solid content concentration was 28%, and in the case of using (meth)acrylic resin 3 or 4, the solid content concentration was 14%. Ethyl acetate was added to prepare a solution of the pressure-sensitive adhesive composition.

The details of each compounding component indicated by abbreviation in Table 2 are as follows.

[Compound (B)]

See Table 3 below.

[Crosslinking agent (C)]

C1: ethyl acetate solution of trimethylolpropane adduct of tolylene diisocyanate (75% solid content concentration), "Colonate L" obtained from Nippon Polyurethane Co., Ltd.;

C2: An isocyanurate form of hexamethylene diisocyanate, a liquid containing almost 100% of the active ingredient, "Colonate HXR" obtained from Nippon Polyurethane Co., Ltd.

[Ionic compound (D)]

AS1: N-octyl-4-methylpyridinium hexafluorophosphate (melting point 44°C)

AS2: quaternary ammonium bis(trifluoromethanesulfonyl)imide (melting point 34°C).

[Silane compound (E)]

S1: 3-glycidoxypropyltrimethoxysilane (liquid), "KBM403" obtained from Shin-Etsu Chemical Industry Co., Ltd.

(2) Production of pressure-sensitive adhesive layer

Each pressure-sensitive adhesive composition prepared in (1) above was applied to the release-treated surface of a separator made of a polyethylene terephthalate film subjected to release treatment ["PLR-382051" obtained from Lintec Co., Ltd.] using an applicator, and the thickness after drying was applied so as to be 20 μm, and dried at 100° C. for 1 minute to prepare a pressure-sensitive adhesive layer (pressure-sensitive adhesive sheet).

(3) Production of a protective film made of (meth)acrylic resin

A copolymer of methyl methacrylate/methyl acrylate (weight ratio 96/4) was prepared as a (meth)acrylic resin. In addition, the innermost layer is a hard polymer polymerized using methyl methacrylate and a small amount of allyl methacrylate, and the middle layer is a soft polymer polymerized using styrene and a small amount of allyl methacrylate with butyl acrylate as the main component. The elastic body, the outermost layer of which is a three-layered elastic body particle composed of a hard polymer polymerized with methyl methacrylate and a small amount of ethyl acrylate, and the average particle diameter to the middle layer of the elastic body of 240 nm was prepared as rubber particles.

A benzotriazole-based ultraviolet absorber was added to pellets in which the above-described (meth)acrylic resin and rubber particles were blended in a weight ratio of the former/the latter = 70/30, while melt-kneading with a twin screw extruder, with respect to 100 parts of the pellets 0.05 stearic acid as a lubricant was added and mixed to obtain pellets of a resin composition. The pellets are fed into a 65 mmφ single screw extruder, extruded through a T-shaped die at a set temperature of 275°C, and both sides of the extruded film-like molten resin are sandwiched between two polishing rolls with mirror surfaces set at a temperature of 45°C for cooling. Thus, a protective film made of a (meth)acrylic resin having a thickness of 75 μm was produced.

(4) Production of polarizing plate with pressure-sensitive adhesive layer

A protective film made of (meth)acrylic resin prepared in (3) above is placed on one side of a polarizer having a thickness of 23 μm in which iodine is adsorbed and oriented on a uniaxially stretched polyvinyl alcohol film, and a cyclic polyolefin resin is placed on the other side. A polarizing plate was produced by bonding retardation films having a thickness of 50 μm through an adhesive. Subsequently, after bonding the surface (surface of the pressure-sensitive adhesive layer) opposite to the separator in the pressure-sensitive adhesive layer produced in the above (2) to the outer surface of the retardation film with a laminator, conditions of a temperature of 23 ° C. and a relative humidity of 65% It cured for 7 days and obtained a polarizing plate with an adhesive layer.

(5) Evaluation of durability

After peeling the separator from the polarizing plate with the pressure-sensitive adhesive layer prepared in (4) above, the surface of the pressure-sensitive adhesive layer was adhered to both sides of a glass substrate for a liquid crystal cell [“Eagle XG” manufactured by Corning Co., Ltd.] so as to be orthogonal to nicol to prepare a sample for evaluation. The following three types of durability tests were conducted using this sample.

[Durability test]

Heat resistance test maintained for 1000 hours under dry conditions at a temperature of 80 ° C,

Moist heat resistance test maintained for 1000 hours under an environment of temperature 60℃ and relative humidity 90%,

· A thermal shock resistance (HS) test in which an operation of holding for 30 minutes under drying conditions at a temperature of 70°C and then holding for 30 minutes under drying conditions at a temperature of -40°C is regarded as one cycle, and this is repeated 500 cycles.

The sample after each test was visually observed, and durability was evaluated according to the following evaluation criteria. Results are shown in Table 4.

A: No change in appearance, such as floating, peeling, or foaming, is observed.

B: Appearance changes such as floating, peeling, and foaming are hardly seen.

C: Appearance changes such as floating, peeling, and foaming are slightly conspicuous,

D: Appearance changes such as floating, peeling, and foaming are remarkably observed.

(6) Evaluation of reworkability

The polarizing plate with the pressure-sensitive adhesive layer produced in the above (4) was cut into a test piece having a size of 25 mm x 150 mm. Next, after peeling the separator from this test piece, the adhesive layer surface was adhered to a glass substrate for a liquid crystal cell [“Eagle XG” manufactured by Corning Co., Ltd.], and auto-attached for 20 minutes at a temperature of 50° C. and a pressure of 5 kg/cm 2 (490.3 kPa). Crave processing was done. Subsequently, after maintaining in an oven at 50 ° C. for 50 hours, in an atmosphere of a temperature of 23 ° C. and a relative humidity of 50%, a polarizing plate was removed from the test piece adhered to the glass substrate in a 180 ° direction at a speed of 300 mm / min for each adhesive layer (polarizing plate A peeling test was performed in which the sheet was peeled in a direction parallel to the glass substrate surface in a state of being peeled off and turned over. The state of the glass substrate surface after the peeling test was visually observed, and reworkability was evaluated according to the following evaluation criteria. Results are shown in Table 4.

A: No dark spots or glue residues are observed on the surface of the glass plate.

B: Almost no dark spots and glue residues are observed on the surface of the glass plate.

C: Glue residue is hardly observed on the surface of the glass plate, but dark areas are observed.

D: Glue residue is confirmed on the surface of the glass plate.

(7) Measurement of the gel fraction of the pressure-sensitive adhesive layer

After leaving the pressure-sensitive adhesive layer (pressure-sensitive adhesive sheet) produced in the above (2) at room temperature for 1 day and after leaving it for 8 days, respectively, the gel fraction was measured. Results are shown in Table 4. The gel fraction was measured according to the following [a] to [d].

[a] A pressure-sensitive adhesive layer having an area of about 8 cm x about 8 cm and a metal mesh made of SUS304 having an area of about 10 cm x about 10 cm (its weight being Wm) are bonded.

[b] The bonded product obtained in [a] is weighed, the weight is taken as Ws, and then folded 4 times in such a way that the pressure-sensitive adhesive layer is wrapped and fixed with a stapler, and then weighed, and the weight is taken as Wb.

[c] Put the mesh stapled in [b] above into a glass container, add 60 mL of ethyl acetate to immerse it, and then store the glass container at room temperature for 3 days.

[d] The mesh is taken out from the glass container, dried at 120 ° C. for 24 hours, and then weighed, the weight is defined as Wa, and the following formula:

Gel fraction (% by weight) = [{Wa-(Wb-Ws)-Wm}/(Ws-Wm)]×100

Calculate the gel fraction based on

(8) Evaluation of antistatic properties of polarizing plate with pressure-sensitive adhesive layer

When the separator of the polarizing plate with the pressure-sensitive adhesive layer produced in the above (4) was peeled off, the surface resistance value of the pressure-sensitive adhesive layer was measured with a surface resistivity measuring device ["Hirest-up MCP-HT450" manufactured by Mitsubishi Chemical Corporation], , and the antistatic property was evaluated. If the surface resistance value is on the order of 10 ¹¹ Ω/□ or less, good antistatic properties can be obtained. Evaluation of antistatic property was performed immediately after curing of the polarizing plate with an adhesive layer was completed. Results are shown in Table 4.

(9) Measurement of peeling force of separator (peeling film)

The polarizing plate with the pressure-sensitive adhesive layer produced in the above (4) was cut into a test piece having a size of 25 mm x 150 mm. Next, a peeling test was conducted in which the separator was peeled from the test piece in the 180° direction at a speed of 300 mm/min in an atmosphere of a temperature of 23°C and a relative humidity of 50%, and the peel force P ₀ of the separator was measured. The peel force P ₁ of the release film after the heating test maintained at 70°C for 20 days was also measured under the same conditions, and the peel force enhancement rate was calculated based on the following formula. Results are shown in Table 4.

Peel force enhancement rate (%) = (P ₁ /P ₀ )×100

<Preparation Example 5: Preparation of (meth)acrylic resin 5 for pressure-sensitive adhesive layer>

120 parts of ethyl acetate was placed in a reaction vessel equipped with a cooling tube, a nitrogen inlet tube, a thermometer and a stirrer, and the air in the apparatus was substituted with nitrogen gas to make it free of oxygen, and then the internal temperature was raised to 75°C. After adding the entire solution of 0.05 parts of azobisisobutyronitrile (polymerization initiator) in 5 parts of ethyl acetate, while maintaining the internal temperature at 74-76 ° C., 50.6 parts of butyl acrylate, 40.0 parts of methyl acrylate, 2-phenoxy acrylate A mixed solution of 4.0 parts of cyethyl, 4.0 parts of 2-hydroxyethyl acrylate, and 1.4 parts of acrylic acid was added dropwise into the reaction system over 2 hours. Further, the reaction was completed by keeping the mixture warm at an internal temperature of 74 to 76°C for 5 hours. Finally, ethyl acetate was added to adjust the concentration of the (meth)acrylic resin to 40% to prepare an ethyl acetate solution of the (meth)acrylic resin 5. The obtained (meth)acrylic resin 5 had a weight average molecular weight (Mw) of 700,000 and Mw/Mn of 5.8.

<Preparation Example 6: Preparation of (meth)acrylic resin 6 for pressure-sensitive adhesive layer>

In a reaction vessel equipped with a cooling tube, a nitrogen inlet tube, a thermometer and a stirrer, 81.8 parts of ethyl acetate, 56.0 parts of butyl acrylate, 35.0 parts of methyl acrylate, 6.0 parts of 2-phenoxyethyl acrylate, 2.0 parts of 2-hydroxyethyl acrylate and acrylic acid 1.0 part of the mixed solution was added, and the air in the apparatus was substituted with nitrogen gas to raise the internal temperature to 55°C while making it oxygen-free. Thereafter, a solution obtained by dissolving 0.14 parts of azobisisobutyronitrile (polymerization initiator) in 10 parts of ethyl acetate was added in its entirety. One hour after the addition of the initiator, ethyl acetate was continuously added into the reaction vessel at an addition rate of 17.3 parts/hr so that the concentration of the (meth)acrylic resin was 35%, and kept warm at an internal temperature of 54 to 56° C. for 12 hours, and finally Ethyl acetate was added thereto to adjust the concentration of (meth)acrylic resin to 20%, thereby obtaining a solution of (meth)acrylic resin 6. The obtained (meth)acrylic resin 6 had a weight average molecular weight (Mw) of 1,540,000 and a molecular weight distribution (Mw/Mn) of 5.8.

<Examples 11 to 22, Comparative Examples 6 to 7>

(1) Preparation of pressure-sensitive adhesive composition

With respect to 100 parts of the solid content of the (meth)acrylic resin (A) obtained in Production Examples 5 to 6, the compounds (B), crosslinking agents (C), ionic compounds (D) and silane compounds (E) shown in Table 5 were mixed in the amounts shown in Table 5, respectively, so that the solid content concentration was 28% when using (meth)acrylic resin 5 and 14% when using (meth)acrylic resin 6, Ethyl acetate was added to prepare a solution of the pressure-sensitive adhesive composition.

Details of the compounds (B) represented by the abbreviations of EO6 to EO9 in Table 5 are shown in Table 6 below. Details of the abbreviations EO3, EO5, C1, AS1 and S1 are as described above.

(2) Production of a polarizing plate with an adhesive layer, and evaluation of durability and reworkability

Using each adhesive composition prepared in (1) above, an adhesive layer (adhesive sheet) was produced in the same procedure as described in (2) in <Examples 1 to 10 and Comparative Examples 1 to 5>. Using this pressure-sensitive adhesive layer and a protective film made of (meth)acrylic resin prepared in (3) in <Examples 1 to 10 and Comparative Examples 1 to 5>, A polarizing plate with an adhesive layer was produced in the same procedure as described in (4) in 1 to 5>. About the obtained polarizing plate with an adhesive layer, durability and reworkability were evaluated according to (5) and (6) in <Examples 1-10 and Comparative Examples 1-5> mentioned above. Results are shown in Table 7.

Claims (15)

delete (Meth) acrylic resin (A) 100 parts by weight,
0.15 to 8 parts by weight of a compound (B) containing at least one double bond and at least one alkylenedioxy group in the molecule
contains,
The compound (B) has the following formula (B-1):

(In the formula, h represents an integer of 1 to 6, Q ¹ represents a hydrogen atom or a methyl group, and Q ⁰ represents an h-valent group having at least one alkylenedioxy group.)
Including the compound (B-1) represented by,
The above Q ⁰ is the following Q ⁰² , Q ⁰³ and Q ⁰⁴ :

(In Q ⁰² , j represents an integer from 1 to 40,
In Q ⁰³ , y and z each independently represent an integer of 1 to 40, y + z is an integer of 1 to 40,
In Q ⁰⁴ , e, f and g each independently represent an integer of 1 to 20, and e+f+g is an integer of 1 to 30.)
A pressure-sensitive adhesive composition selected from at least one group represented by. delete delete delete (Meth) acrylic resin (A) 100 parts by weight,
0.15 to 8 parts by weight of a compound (B) containing at least one double bond and at least one alkylenedioxy group in the molecule
contains,
The compound (B) has the following formula (B-1):

(In the formula, h represents an integer of 1 to 6, Q ¹ represents a hydrogen atom or a methyl group, and Q ⁰ represents an h-valent group having at least one alkylenedioxy group.)
Including the compound (B-1) represented by,
The compound (B-1) is a compound (B-1a) represented by the following formula (B-1a):

(Wherein, Q ¹ represents a hydrogen atom or a methyl group, L represents a single bond or an alkylene group having 1 to 4 carbon atoms, i represents an integer of 1 to 50, and Q ² is substituted with an alkoxy group having 1 to 3 carbon atoms, Represents an alkyl group, aryl group or aralkyl group having 1 to 4 carbon atoms, which may be present.) delete delete delete A pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition according to claim 2 or 6. An optical member with a pressure-sensitive adhesive layer comprising an optical member and the pressure-sensitive adhesive layer according to claim 10 laminated thereon. The optical member with an adhesive layer according to claim 11, wherein the optical member includes a polarizer. The optical member with an adhesive layer according to claim 11, further comprising a release film laminated on an outer surface of the adhesive layer. The method according to claim 13, when the peeling force of the peeling film after a heating test maintained at 70 ° C. for 20 days is P ₁ and the peeling force before the heating test is P ₀ , the peel force enhancement rate defined by the following formula is 200% The following optical members with an adhesive layer:
Peel force enhancement rate (%) = (P ₁ /P ₀ )×100 The optical member with an adhesive layer according to claim 11, further comprising a glass substrate laminated on an outer surface of the pressure-sensitive adhesive layer.

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